Apparatus for forming folded food products are known (see, for instance, the machine described in U.S. Pat. No. 5,912,035, the disclosure of which is incorporated herein by reference in its entirety). In the burrito-folding machine and associated method of the '035 Patent, which is owned by the assignee of the present application, a tortilla (or shell) is placed upon a substantially circular folding platform 10, such as is shown in FIG. 1, for subsequent filling and folding steps. The folding platform 10 includes a substantially planar base 12, a first flap 14 pivotally mounted to the base 12 via a first hinge 16, a second flap 18 pivotally mounted to the base 12 via a second hinge 20, and a third flap 22 pivotally mounted to the base 12 via a third hinge 24. The folding platform 10 further includes a channel-shaped depression 26 formed from corresponding portions of the base 12 and the second and third flaps 18, 22.
Referring to FIG. 2a, filling and folding of a tortilla 28 begins with the tortilla 28 being placed or draped on the folding platform 10 in a more or less centered position, after which a portion 30 of a food filling is deposited on the tortilla 28 above the approximate location of the depression 26 in the base 12. As shown in FIG. 2b, the first flap 14 of the folding table 10 is initially actuated by being rotated/overturned about the first hinge 16 in a pivoting motion (not shown) with respect to the base 12, after which the first flap 14 is returned to its starting position shown both in FIG. 1 and FIG. 2b. This causes a first side 32 of the tortilla 28 to be folded more or less entirely over the food filling portion 30, thereby creating a first fold 34 in the tortilla 28. Next, and as shown in FIG. 2c, the second and third flaps 18, 22 of the folding table 10 are actuated by being rotated/overturned about their respective second and third hinges 20, 24 in separate sequential pivoting motions (not shown) with respect to the base 12, after which the second and third flaps 18, 22 are returned to their starting positions (shown in both FIG. 1 and FIG. 2c). These actuations cause opposite second and third sides 36, 38 of the tortilla 28 to be folded both toward each other and on top of the previously-folded first side of the tortilla 28, thereby creating respective second and third folds 40, 42 in the tortilla 28. A conveyor (not shown) carries the partially-folded burrito to an adjustable driven roller (not shown) that applies slight pressure to (i.e., pinches) the partially-folded burrito. A set of folding jaws (not shown) then engages and rotates the partially-folded burrito to complete the folding of the finished burrito.
While the automated machine and method of the '035Patent alleviate many of the problems associated with manual burrito folding, other problems exist as a result of the automated operation. In particular, in the process of transferring the partially-folded burrito from the folding platform 10 to the adjustable driven roller (not shown), one or more of the folded sides 32, 36, 38 of the burrito can tend to become unfolded. Even if no unfolding occurs, the multi-step manipulation of the partially-folded burrito may dislodge some of the filling from the unfolded side of the burrito (i.e., the side opposite the first side 32). Either of these occurrences can result in the inferior or incomplete wrapping of the burrito, thereby compromising the automated burrito-making process.